The present invention relates to a system for manufacturing an emulsified/dispersed liquid by emulsifying or dispersing predetermined materials into a medium liquid, in particular relates to a system for manufacturing an emulsified/dispersed liquid by applying a strong shearing force to a liquid mixture containing the medium liquid and the emulsification/dispersion material of solid state or liquid state which is not soluble into the medium liquid so as to emulsify or disperse the emulsification/dispersion material into the medium liquid fundamentally without using surfactants.
Generally, various surfactants are used when producing emulsified/dispersed liquid through emulsification or dispersion of a solid or liquid material into the medium liquid. However, when there is a possible human contact with the emulsified/dispersed liquid (for example, when the liquid is in foods or cosmetics), the surfactants may be harmful. To avoid the use of surfactants, various emulsification/dispersion devices are proposed. These devices focus on emulsifying or dispersing the medium liquid by adding a strong shearing force to the liquid material of medium liquid and liquid of solid form of emulsification/dispersion material that does not dissolve in medium liquid (for example, refer to JP 8-89774 A and WO 2003/059497).
With this type of emulsification/dispersion device, for example, the “high pressured jet” version or the “rotary churning” version of the emulsification/dispersion device is well known. For instance, with the high pressured jet version of the emulsification/dispersion device, highly pressured liquid mixture is sprayed through a nozzle, creating a jet stream. This stream is then clashed against the wall or turns around at the wall, and the liquid/liquid junction converts the kinetic energy of the jet stream into the shearing force energy required for the emulsification/dispersion process.
However, if the strong shearing force is applied to the liquid mixture in an unbalanced environment (namely, if an unbalanced pressure or speed exists), then the dissolved gas or the gas left within the medium liquid will turn into bubbles and the liquid mixture will begin bubbling. Due to these bubbling, excessive amounts of emulsification/dispersion material particles will be produced. To prevent such occurrence, the emulsification/dispersion device places back pressure on either the liquid mixture or the emulsified/dispersed liquid, in order to avoid bubbling from taking place.
Recent years at the market, highly emulsifible or dispersible material of the emulsified/dispersed liquid (namely, emulsified/dispersed liquid with extremely atomized emulsification/dispersion material) is demanded. To produce such liquid, a new emulsification/dispersion device is being developed. This device applies higher pressure to either medium liquid or liquid mixture in hopes of atomizing the emulsification/dispersion material. The only flaw of this device is that the occurrence of bubbling becomes a serious problem. Even though the increase of back pressure upon the liquid mixture or the emulsified/dispersed liquid prevented bubbling from occurring, this new process causes bubbling to occur due to an instant pressure depletion when the emulsified/dispersed liquid is drained from the emulsification/dispersion device.
If bubbling occurs within the emulsified/dispersed liquid, in the case of dispersing powder material on the medium liquid, air bubbles will stick upon the powder surface, and the wettability of the powder will worsen. In the case of emulsion, aerosol is easily formed, and the quality as a product of emulsified/dispersed liquid deteriorates. Also, energy losses will increase and energy efficiency will worsen because the created air bubbles absorb energy. In addition, if (for instance) an unsaturated fatty acid is used as an emulsification/dispersion material, the material will oxidize under the high temperature due to the oxygen within the air bubble. As a result, the products' qualities will deteriorate.